What’s that you’re doing, Ms. Hanke?

“Many of the tools and components we use are so specialized that we cannot just buy them from suppliers but have to make them ourselves. This usually requires drills, lathes and milling machines. Part of my apprenticeship involves learning exactly how this is done. The foreman hands me a technical drawing and I get started. Right now I’m making a threaded bore, that’s an elongated hole with a screw thread. It’s just a routine job, a matter of practice. My main tool is naturally a drill. First step: Find the right sized drill bit and drill the hole. Second step: Attach something called a counterbore and drill the cut-out into which the head of the screw will slot so that it’s flush with the surface – you don’t want to have it sticking out. Done? Not quite, because the inside of the hole is still smooth. The last step is to use a tap to cut fine grooves into the inside wall of the hole – to guide the screw.”